With increasing emphasis on water conservation, there is renewed interest in toilets and urinals designed to minimize the amount of water consumed in flushing to mitigate excessive demands on water supplies as well as on wastewater disposal systems, both of which have tended to become overloaded with increasing populations.
Sanitation codes require urinals to provide an odor seal to contain gasses and odors which develop in the drain system: this function is conventionally performed by the well known P-trap or S-trap in which the seal is formed by a residual portion of the flushing water. This seal effectively locks in sewer odors from the drainpipe beyond the trap, however the upward-facing liquid surface communicates freely with the user environment, so that the trap must be kept free of residual urine by copious flushing to prevent unacceptable odor levels from the liquid in the trap; therefore a large amount of water is consumed in flushing these conventional urinals. Especially in the U.S. over many years when water was cheap and plentiful, conventional flushing type urinals and water-wasteful toilets held an unchallenged monopoly. However more recently, threatened and real water shortages have aroused new environmental concerns and heightened conservation awareness as evidenced by the introduction of low flush toilets.
As the cost of water increases and budgets tighten, the prospect of a viable waterless urinal system becomes extremely attractive to a wide range of public agencies, cities, states, penal institutions, defence establishments, recreational and parks departments and the like. Waterless urinals utilizing oil-sealed odor traps are becoming viable. However, the present inventor has discovered that a key factor in their potential is the attainment of low maintenance, and that this is largely dependent on the longevity of the liquid sealant, which in turn is related to the internal structure of the odor trap. Thus, the present inventor has recognized that improvements are desirable both in the rate of depletion under normal service conditions and in protection against catastrophic sealant loss due to high pressure water flushing, which though not required, can occur inadvertently.
It is a primary object of the present invention to provide an improved oil sealed odor trap for a flushless urinal or an anti-evaporation floor drain that not only meets the usual objectives of eliminating the need for a P-trap in the drain line while complying with U.S. sanitation standards, being economical and easy to manufacture and install, and performing reliably and efficiently with low maintenance requirements, but more particularly with regard to depletion of oily liquid sealant, it is a primary object to structure the trap in a manner to largely prevent escape of sealant by causing stray droplets of sealant drifting buoyantly in the flow path to return to the main sealant body.
It is a further object to configure the odor trap such that it can be easily installed and removed from a permanent drain terminal plumbing fixture.
It is still further object that the odor trap should be constructed and arranged to prevent loss of sealant in the event of high pressure flushing with water.